I don't live in the Uk but it is fairly easy to change the end.bit into one that will work. You might even use one from a broken appliance. One thine that you may want to check os the voltage the bulb takes. If it takes normal wall voltage then you should be fine, if not I would suggest an led light that you would normally screw into the lights.

Some of my worst electrical experiences have been with cheap christmas lights. I was given some USB-powered lights as a present, and found that when I plugged them into my PC it crashed it instantly. Every PC I've tried plugging them into crashed immediately, which I assume must be because there's a dead short across the USB power rails. This seems to be because the lightbulbs have two hair-thin bare wires as contacts, but the circular bases mean it's very easy for one to get rotated and twist a single wire across both terminals.

(I could complain about 19th-century filament bulb technology in christmas lights in the 21st century and all the problems they cause but it's not really worth it)